const width = 960, height = 540;

var svg = d3.select("#graph").append("svg")
            .attr("viewBox", "0 0 "+width+" "+height);

// var svg = d3.select("svg"),
//     width = +svg.attr("width"),
//     height = +svg.attr("height"),
angles = d3.range(0, 2 * Math.PI, Math.PI / 200);

var path = svg.append("g")
    .attr("transform", "translate(" + width / 2 + "," + height / 2 + ")")
    .attr("fill", "none")
    .attr("stroke-width", 10)
    .attr("stroke-linejoin", "round")
  .selectAll("path")
  .data(["cyan", "magenta", "yellow"])
  .enter().append("path")
    .attr("stroke", function(d) { return d; })
    .style("mix-blend-mode", "darken")
    .datum(function(d, i) {
      return d3.radialLine()
          .curve(d3.curveLinearClosed)
          .angle(function(a) { return a; })
          .radius(function(a) {
            var t = d3.now() / 1000;
            return 200 + Math.cos(a * 8 - i * 2 * Math.PI / 3 + t) * Math.pow((1 + Math.cos(a - t)) / 2, 3) * 32;
          });
    });

d3.timer(function() {
  path.attr("d", function(d) {
    return d(angles);
  });
});